What is the difference between structure and table?

For me, they looks very similar. I'm not sure when I should use table or structure.

Structure

Table

Answer 1

[Walter Roberson]

table has a nicer output presentation, and should be more efficient in memory. It also has some useful operations especially when you start getting into timetable objects.

table makes it easier to select subsets of the data. For example you might want to select the excitation and fft of all the entries on a particular date. With struct you would do something like construct mask to select particular structure entries and then do

   out = struct('excitation', S(mask).excitation, 'fft', S(mask).fft);

Whereas with tables it would be

out = T(mask, {'excitation', 'fft'}) ;

Or

out = T(mask, [4,7]);

However, table are slower than structures.

[Francesco Giuseppe Fornari]

Hi,

What's the meaning of this command you wrote? is mask a table variable?

Thanks

[Walter Roberson]

mask here is either a logical vector or a vector of indices, that you have constructed before this according to which entries you wish to select. For example,

now = datetime('now');
dates = [S.date];
mask = dates >= now - days(31);
out = struct('excitation', S(mask).excitation, 'fft', S(mask).fft);

or for tables,

now = datetime('now');
mask = T.dates >= now - days(31);
out = T(mask, {'excitation', 'fft'});